TYPO3 Core

Thanks for creating the feature request.

The current implementation can fetch any files from an available storage, including a file picker. By allowing a syntax like EXT: would also require us to remove the inputLinkField with all the preview functionality which was highly appreciated in the community. Furthermore it is very errorprone.

We reject the issue therefore. If you need to use files from an extension, you could still create a file mount pointing to e.g. Resources/Public directory of an extension.